332 lines
9.1 KiB
C
332 lines
9.1 KiB
C
/****************************************************************************
|
|
|
|
Copyright Echo Digital Audio Corporation (c) 1998 - 2004
|
|
All rights reserved
|
|
www.echoaudio.com
|
|
|
|
This file is part of Echo Digital Audio's generic driver library.
|
|
|
|
Echo Digital Audio's generic driver library is free software;
|
|
you can redistribute it and/or modify it under the terms of
|
|
the GNU General Public License as published by the Free Software
|
|
Foundation.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 59 Temple Place - Suite 330, Boston,
|
|
MA 02111-1307, USA.
|
|
|
|
*************************************************************************
|
|
|
|
Translation from C++ and adaptation for use in ALSA-Driver
|
|
were made by Giuliano Pochini <pochini@shiny.it>
|
|
|
|
****************************************************************************/
|
|
|
|
|
|
/******************************************************************************
|
|
MIDI lowlevel code
|
|
******************************************************************************/
|
|
|
|
/* Start and stop Midi input */
|
|
static int enable_midi_input(struct echoaudio *chip, char enable)
|
|
{
|
|
DE_MID(("enable_midi_input(%d)\n", enable));
|
|
|
|
if (wait_handshake(chip))
|
|
return -EIO;
|
|
|
|
if (enable) {
|
|
chip->mtc_state = MIDI_IN_STATE_NORMAL;
|
|
chip->comm_page->flags |=
|
|
__constant_cpu_to_le32(DSP_FLAG_MIDI_INPUT);
|
|
} else
|
|
chip->comm_page->flags &=
|
|
~__constant_cpu_to_le32(DSP_FLAG_MIDI_INPUT);
|
|
|
|
clear_handshake(chip);
|
|
return send_vector(chip, DSP_VC_UPDATE_FLAGS);
|
|
}
|
|
|
|
|
|
|
|
/* Send a buffer full of MIDI data to the DSP
|
|
Returns how many actually written or < 0 on error */
|
|
static int write_midi(struct echoaudio *chip, u8 *data, int bytes)
|
|
{
|
|
if (snd_BUG_ON(bytes <= 0 || bytes >= MIDI_OUT_BUFFER_SIZE))
|
|
return -EINVAL;
|
|
|
|
if (wait_handshake(chip))
|
|
return -EIO;
|
|
|
|
/* HF4 indicates that it is safe to write MIDI output data */
|
|
if (! (get_dsp_register(chip, CHI32_STATUS_REG) & CHI32_STATUS_REG_HF4))
|
|
return 0;
|
|
|
|
chip->comm_page->midi_output[0] = bytes;
|
|
memcpy(&chip->comm_page->midi_output[1], data, bytes);
|
|
chip->comm_page->midi_out_free_count = 0;
|
|
clear_handshake(chip);
|
|
send_vector(chip, DSP_VC_MIDI_WRITE);
|
|
DE_MID(("write_midi: %d\n", bytes));
|
|
return bytes;
|
|
}
|
|
|
|
|
|
|
|
/* Run the state machine for MIDI input data
|
|
MIDI time code sync isn't supported by this code right now, but you still need
|
|
this state machine to parse the incoming MIDI data stream. Every time the DSP
|
|
sees a 0xF1 byte come in, it adds the DSP sample position to the MIDI data
|
|
stream. The DSP sample position is represented as a 32 bit unsigned value,
|
|
with the high 16 bits first, followed by the low 16 bits. Since these aren't
|
|
real MIDI bytes, the following logic is needed to skip them. */
|
|
static inline int mtc_process_data(struct echoaudio *chip, short midi_byte)
|
|
{
|
|
switch (chip->mtc_state) {
|
|
case MIDI_IN_STATE_NORMAL:
|
|
if (midi_byte == 0xF1)
|
|
chip->mtc_state = MIDI_IN_STATE_TS_HIGH;
|
|
break;
|
|
case MIDI_IN_STATE_TS_HIGH:
|
|
chip->mtc_state = MIDI_IN_STATE_TS_LOW;
|
|
return MIDI_IN_SKIP_DATA;
|
|
break;
|
|
case MIDI_IN_STATE_TS_LOW:
|
|
chip->mtc_state = MIDI_IN_STATE_F1_DATA;
|
|
return MIDI_IN_SKIP_DATA;
|
|
break;
|
|
case MIDI_IN_STATE_F1_DATA:
|
|
chip->mtc_state = MIDI_IN_STATE_NORMAL;
|
|
break;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
/* This function is called from the IRQ handler and it reads the midi data
|
|
from the DSP's buffer. It returns the number of bytes received. */
|
|
static int midi_service_irq(struct echoaudio *chip)
|
|
{
|
|
short int count, midi_byte, i, received;
|
|
|
|
/* The count is at index 0, followed by actual data */
|
|
count = le16_to_cpu(chip->comm_page->midi_input[0]);
|
|
|
|
if (snd_BUG_ON(count >= MIDI_IN_BUFFER_SIZE))
|
|
return 0;
|
|
|
|
/* Get the MIDI data from the comm page */
|
|
i = 1;
|
|
received = 0;
|
|
for (i = 1; i <= count; i++) {
|
|
/* Get the MIDI byte */
|
|
midi_byte = le16_to_cpu(chip->comm_page->midi_input[i]);
|
|
|
|
/* Parse the incoming MIDI stream. The incoming MIDI data
|
|
consists of MIDI bytes and timestamps for the MIDI time code
|
|
0xF1 bytes. mtc_process_data() is a little state machine that
|
|
parses the stream. If you get MIDI_IN_SKIP_DATA back, then
|
|
this is a timestamp byte, not a MIDI byte, so don't store it
|
|
in the MIDI input buffer. */
|
|
if (mtc_process_data(chip, midi_byte) == MIDI_IN_SKIP_DATA)
|
|
continue;
|
|
|
|
chip->midi_buffer[received++] = (u8)midi_byte;
|
|
}
|
|
|
|
return received;
|
|
}
|
|
|
|
|
|
|
|
|
|
/******************************************************************************
|
|
MIDI interface
|
|
******************************************************************************/
|
|
|
|
static int snd_echo_midi_input_open(struct snd_rawmidi_substream *substream)
|
|
{
|
|
struct echoaudio *chip = substream->rmidi->private_data;
|
|
|
|
chip->midi_in = substream;
|
|
DE_MID(("rawmidi_iopen\n"));
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
static void snd_echo_midi_input_trigger(struct snd_rawmidi_substream *substream,
|
|
int up)
|
|
{
|
|
struct echoaudio *chip = substream->rmidi->private_data;
|
|
|
|
if (up != chip->midi_input_enabled) {
|
|
spin_lock_irq(&chip->lock);
|
|
enable_midi_input(chip, up);
|
|
spin_unlock_irq(&chip->lock);
|
|
chip->midi_input_enabled = up;
|
|
}
|
|
}
|
|
|
|
|
|
|
|
static int snd_echo_midi_input_close(struct snd_rawmidi_substream *substream)
|
|
{
|
|
struct echoaudio *chip = substream->rmidi->private_data;
|
|
|
|
chip->midi_in = NULL;
|
|
DE_MID(("rawmidi_iclose\n"));
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
static int snd_echo_midi_output_open(struct snd_rawmidi_substream *substream)
|
|
{
|
|
struct echoaudio *chip = substream->rmidi->private_data;
|
|
|
|
chip->tinuse = 0;
|
|
chip->midi_full = 0;
|
|
chip->midi_out = substream;
|
|
DE_MID(("rawmidi_oopen\n"));
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
static void snd_echo_midi_output_write(unsigned long data)
|
|
{
|
|
struct echoaudio *chip = (struct echoaudio *)data;
|
|
unsigned long flags;
|
|
int bytes, sent, time;
|
|
unsigned char buf[MIDI_OUT_BUFFER_SIZE - 1];
|
|
|
|
DE_MID(("snd_echo_midi_output_write\n"));
|
|
/* No interrupts are involved: we have to check at regular intervals
|
|
if the card's output buffer has room for new data. */
|
|
sent = bytes = 0;
|
|
spin_lock_irqsave(&chip->lock, flags);
|
|
chip->midi_full = 0;
|
|
if (!snd_rawmidi_transmit_empty(chip->midi_out)) {
|
|
bytes = snd_rawmidi_transmit_peek(chip->midi_out, buf,
|
|
MIDI_OUT_BUFFER_SIZE - 1);
|
|
DE_MID(("Try to send %d bytes...\n", bytes));
|
|
sent = write_midi(chip, buf, bytes);
|
|
if (sent < 0) {
|
|
snd_printk(KERN_ERR "write_midi() error %d\n", sent);
|
|
/* retry later */
|
|
sent = 9000;
|
|
chip->midi_full = 1;
|
|
} else if (sent > 0) {
|
|
DE_MID(("%d bytes sent\n", sent));
|
|
snd_rawmidi_transmit_ack(chip->midi_out, sent);
|
|
} else {
|
|
/* Buffer is full. DSP's internal buffer is 64 (128 ?)
|
|
bytes long. Let's wait until half of them are sent */
|
|
DE_MID(("Full\n"));
|
|
sent = 32;
|
|
chip->midi_full = 1;
|
|
}
|
|
}
|
|
|
|
/* We restart the timer only if there is some data left to send */
|
|
if (!snd_rawmidi_transmit_empty(chip->midi_out) && chip->tinuse) {
|
|
/* The timer will expire slightly after the data has been
|
|
sent */
|
|
time = (sent << 3) / 25 + 1; /* 8/25=0.32ms to send a byte */
|
|
mod_timer(&chip->timer, jiffies + (time * HZ + 999) / 1000);
|
|
DE_MID(("Timer armed(%d)\n", ((time * HZ + 999) / 1000)));
|
|
}
|
|
spin_unlock_irqrestore(&chip->lock, flags);
|
|
}
|
|
|
|
|
|
|
|
static void snd_echo_midi_output_trigger(struct snd_rawmidi_substream *substream,
|
|
int up)
|
|
{
|
|
struct echoaudio *chip = substream->rmidi->private_data;
|
|
|
|
DE_MID(("snd_echo_midi_output_trigger(%d)\n", up));
|
|
spin_lock_irq(&chip->lock);
|
|
if (up) {
|
|
if (!chip->tinuse) {
|
|
init_timer(&chip->timer);
|
|
chip->timer.function = snd_echo_midi_output_write;
|
|
chip->timer.data = (unsigned long)chip;
|
|
chip->tinuse = 1;
|
|
}
|
|
} else {
|
|
if (chip->tinuse) {
|
|
chip->tinuse = 0;
|
|
spin_unlock_irq(&chip->lock);
|
|
del_timer_sync(&chip->timer);
|
|
DE_MID(("Timer removed\n"));
|
|
return;
|
|
}
|
|
}
|
|
spin_unlock_irq(&chip->lock);
|
|
|
|
if (up && !chip->midi_full)
|
|
snd_echo_midi_output_write((unsigned long)chip);
|
|
}
|
|
|
|
|
|
|
|
static int snd_echo_midi_output_close(struct snd_rawmidi_substream *substream)
|
|
{
|
|
struct echoaudio *chip = substream->rmidi->private_data;
|
|
|
|
chip->midi_out = NULL;
|
|
DE_MID(("rawmidi_oclose\n"));
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
static struct snd_rawmidi_ops snd_echo_midi_input = {
|
|
.open = snd_echo_midi_input_open,
|
|
.close = snd_echo_midi_input_close,
|
|
.trigger = snd_echo_midi_input_trigger,
|
|
};
|
|
|
|
static struct snd_rawmidi_ops snd_echo_midi_output = {
|
|
.open = snd_echo_midi_output_open,
|
|
.close = snd_echo_midi_output_close,
|
|
.trigger = snd_echo_midi_output_trigger,
|
|
};
|
|
|
|
|
|
|
|
/* <--snd_echo_probe() */
|
|
static int __devinit snd_echo_midi_create(struct snd_card *card,
|
|
struct echoaudio *chip)
|
|
{
|
|
int err;
|
|
|
|
if ((err = snd_rawmidi_new(card, card->shortname, 0, 1, 1,
|
|
&chip->rmidi)) < 0)
|
|
return err;
|
|
|
|
strcpy(chip->rmidi->name, card->shortname);
|
|
chip->rmidi->private_data = chip;
|
|
|
|
snd_rawmidi_set_ops(chip->rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
|
|
&snd_echo_midi_input);
|
|
snd_rawmidi_set_ops(chip->rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
|
|
&snd_echo_midi_output);
|
|
|
|
chip->rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT |
|
|
SNDRV_RAWMIDI_INFO_INPUT | SNDRV_RAWMIDI_INFO_DUPLEX;
|
|
DE_INIT(("MIDI ok\n"));
|
|
return 0;
|
|
}
|